1. Field the Invention
The present invention deals with a solid triglyceride fat which is suited to be used as a hardstock fat for the preparation of emulsion spreads and with a process for the preparation of such fat.
2. Description of Related Art
Margarine is an edible emulsion spread consisting of a continuous fat phase and an aqueous phase which is dispersed as fine droplets in the fat phase. The fat phase of margarine and of similar fat continuous emulsion spreads is a mixture of a fat which is fully liquid (the oil part of the fat phase) and a fat which is solid at ambient temperature. For imparting to common margarine a semi-solid, plastic, spreadable consistency this stabilizing and structuring hardstock functionality plays an important role. The crystals of the solid fat denoted as hardstock fat, form a network throughout the liquid oil resulting into a structured fat phase. It also helps to stabilize the emulsion. Because the aqueous phase droplets are fixed within the spaces of the lattice of solid fat crystals, coalescence of the droplets and separation of the heavier aqueous phase from the fat phase is prevented.
The technology of spread processing is well established. The type of fat and the ratio of liquid oil and solid fat are chosen such that after proper processing of the fat blend with an aqueous phase a plastic product with a suitable consistency and mouthfeel is obtained.
Unprocessed liquid vegetable oils are the major ingredient in the composition of margarine fats. Vegetable fats are preferred over animal fats because their high content of unsaturated fatty acid residues enhances the spread's nutritional value. Besides that, vegetable fats are an abundant and relatively cheap resource.
According to the state of the art, the proper functionality of hardstock fats is obtained by subjecting a vegetable fat to a more or less complex process comprising treatments such as blending, fractionation, hydrogenation and interesterification.
Admixing a hardstock fat to a liquid oil aims at obtaining such fat phase that after emulsifying with an aqueous phase and proper cooling and working, a semi-solid, plastic W/O-emulsion results which is easily spreadable, stable at ambient temperatures and which when swallowed gives a pleasant sensory sensation (mouthfeel). The mouthfeel is the overall perception of quick fat melting and the taste of the aqeouos phase which is released during mastication.
It is known that the presence of HMH and HHM triglycerides contributes to a good mouthfeel. H and M denote the fatty acid residues attached to the glyceride backbone, where H means a saturated fatty acid residue having a chain length larger than 15 carbon atoms and M means a saturated fatty acid residue having a chain length of either 12 or 14 carbon atoms placed either in the middle or one of the terminal positions.
Generally, hardstock fats fail to conserve a proper spread consistency when ambient temperatures rise above average. Relying on a higher melting hardstock fat is at variance with the desire of a good oral melt. A waxy mouthfeel is the consequence which is ascribed to the presence of the high melting HHH triglycerides.
The present invention addresses the desire to combine a good oral melt with good consistency even at high ambient temperatures. Particularly at low fat levels such combination could not have been realised.
A good heat stability is shown by the spreads described in EP 0470658. The fat phase contains 6 wt. % of a single fat, fully hydrogenated palm oil or fish oil as hardstock fat. Nearly 6 wt. % of the fat phase necessarily consists of HHH triglycerides. Consequently the resulting spreads show good heat stability but a waxy mouthfeel.
To the contrary a good mouthfeel is reported for the spreads obtained with the fat phase as described in e.g. EP 0089082 which discloses fats with a high content of HMH and HHM triglycerides. Spreads containing such fats are known to be not stable at high ambient temperatures.
The stability problem becomes particularly serious when the fat content of a W/O-spread drops below 55 wt. % and particularly below 40 wt. %. Ordinary hardstock fats increasingly fail to provide heat stability without sacrificing acceptable mouthfeel.
The challenge to comply with the requirements of both good heat stability and quick mouth melting has triggered investigations which have resulted in the present invention.